Sex during period. If cell development continues and a blastocyst implants in the uterusit will become an embryo and create a pregnancy. RT YaleNeuro: Click one of the letters above to advance the page to terms beginning with that letter. Go to top R racism Prejudice, discrimination and oppression based on race or perceived or assigned race. A chosen or felt lack of gender identity. Thank you for some other great post. Use of the mouth, lips or tongue for sexual stimulation. So do what feels right to you.